Selective Torques: How to Treat Cases in Less Time and with More Control

One of the biggest advantages of the passive self-ligation Damon System is the ability to maintain play in the mechanical system during all phases of treatment. It has become very apparent that it is undesirable to totally seat the archwire against the base of the archwire slot during orthodontic treatment with very few exceptions.

With conventional mechanics and active self-ligation, the archwire is totally seated against the base of the bracket slot during some or all phases of treatment. This binding and friction obviously makes closing spaces, leveling, arch form changes, closing openbites and the finishing, settling and detailing of the occlusion far more challenging.

To best utilize the clinical advantage of passive self-ligation brackets, it is strongly recommended not to exceed .019 x .025 archwire dimension in an .022 bracket slot. This needed play allows for 7° of torque play in both directions.

The intent of using multiple bracket torques is to help maintain torque control while keeping play in the mechanical system. The impact of using selective torques is shorter treatment times through greater torque control.

The following Damon prescription is recommended:

U1 – Upper Central Incisors

12° Torque 5° Tip 0° Rotation

• The standard torque prescription selected when central incisors are in good position with minimal requirements for treatment mechanics

17° Torque 5° Tip 0° Rotation

• Selected for division 2 cases
• Cases needing extensive Class II elastics – prevents loss of torque control resulting from elastic wear
• Most extraction cases to prevent loss of torque control when retracting anterior teeth

7° Torque 5° Tip 0° Rotation

• Centrals requiring extensive uprighting
• Case needing extensive Class III elastics – prevents loss of torque control resulting from elastic wear
• Extreme crowding cases combined with anterior tongue thrusting or thumb – finger habit
• Where extensive arch length needs to be gained and the incisors have near normal torque angulation

U2 – Upper Lateral Incisors

8° Torque 9° Tip 0° Rotation

• The standard torque prescription selected when central incisors are in good position with minimal requirements for treatment mechanics

10° Torque 9° Tip 0° Rotation

• Selected for division 2 cases
• Cases needing extensive Class II elastics – prevents loss of torque control resulting from elastic wear
• Most extraction cases to prevent loss of torque control when retracting anterior teeth

3° Torque 9° Tip 0° Rotation

• Centrals requiring extensive uprighting
• Central incisors that are blocked in lingual crossbite that will have too much torque as they move into normal position
• Case needing extensive Class III elastics – prevents loss of torque control resulting from elastic wear
• Extreme crowding cases combined with anterior tongue thrusting or thumb – finger habit
• Where extensive arch length needs to be gained and the incisors have near normal torque angulation

U3 – Upper Cuspids

0° Torque 6° Tip 0° Rotation

• The standard torque prescription selected when the cuspids are in good position or labially inclined

7° Torque 6° Tip 0° Rotation

• Any cuspid needing coronal uprighting
• Most extraction cases requiring first bicuspid space closure – Prevents the cuspid crown from tipping lingual during space closure and helps position the root in medullary bone and away from the cortical plate

U4 & 5 – Upper First and Second Bicuspids

-7° Torque 2° Tip 0° Rotation

• The standard torque prescription selected for all upper first and second bicuspids

U6 – Upper First Molar

-18° Torque 0° Tip 12° Rotation

• The standard torque prescription selected for all upper first molars

U7 – Upper Second Molar

-27° Torque 0° Tip 6° Rotation

• The standard torque prescription selected for all upper second molars – This accent bracket is designed for easy archwire insertion

L1 & 2 – Lower Central and Lateral Incisors

-1° Torque 2° Tip 0° Rotation

• The standard torque prescription selected for all lower central and lateral incisors with minimal requirements for treatment mechanics
• Most extraction cases to prevent loss of torque control when retracting anterior teeth

-6° Torque 2° Tip 0° Rotation

• Extreme crowding in the lower anterior segment
• Cases needing extensive Class II elastics – prevents loss of torque control resulting from elastic wear (mentalis and orbicularis oris muscles also aid in controlling torque of the lower anteriors)
• Any incisor locked lingual with labial root position
• Cases needing a Herbst®* attached to the archwire

L3 – Lower Cuspids

0° Torque 5° Tip 0° Rotation

• The standard torque prescription selected when the cuspids are in good position or labially inclined

7° Torque 5° Tip 0° Rotation

• Any cuspid needing coronal uprighting
• Most extraction cases requiring first bicuspid space closure – Prevents the cuspid crown from tipping lingual during space closure and helps position the root in medullary bone and away from the cortical plate

L4 – Lower First Bicuspids

-12° Torque 2° Tip 0° Rotation

• The standard torque prescription selected for all lower first bicuspids

L5 – Lower Second Bicuspids

-17° Torque 2° Tip 0° Rotation

• The standard torque prescription selected for all lower second bicuspids

L6 – Lower First Molars

-28° Torque 2° Tip 2° Rotation

• The standard torque prescription selected for all lower first molars

L7 – Lower Second Molars

-10° Torque 0° Tip 5° Rotation

• The standard torque prescription selected for all lower second molars (Second molars usually require uprighting – using -10° torque with 7° of tube and archwire play finishes the second molar at a net 17° to 18°)